: I am installing a pressurized water system in my summer home and have mounted the jet pump / pressure tank at floor level. Can I get away with mounting a 10 gallon hot water tank directly above it or will I run into problems with the hot water siphoning backward down the line and putting pressure back on the air pressure tank?

The ten gallon tank will siphon back down to reach gravity level. You can install a check valve on the supply line to overcome the siphon. but it needs to be plumbed level. You can install a backflow prevention valve, also. which allows the cold to be pressure fed into the hot water heater only from one direction.